When H_SMRAME is 1, low memory at 0xa0000 is left alone by
SMM, and instead the chipset maps the 0xa0000-0xbffff window at
0xfeda0000-0xfedbffff. This affects both the "non-SMM" view controlled
by D_OPEN and the SMM view controlled by G_SMRAME, so add two new
MemoryRegions and toggle the enabled/disabled state of all four
in mch_update_smram.
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>